pyexchange get_user_availability

def get_user_availability(mail, start, end, format=u"Default", time_zone='Europe/Moscow'):
    """
    https://msdn.microsoft.com/en-us/library/aa564001(v=exchg.140).aspx

    <?xml version="1.0" encoding="utf-8"?>
    <soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                   xmlns:xsd="http://www.w3.org/2001/XMLSchema"
                   xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"
                   xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types">
      <soap:Body>
        <GetUserAvailabilityRequest xmlns="http://schemas.microsoft.com/exchange/services/2006/messages"
                    xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types">

          <t:TimeZone xmlns="http://schemas.microsoft.com/exchange/services/2006/types">
            <Bias>480</Bias>
            <StandardTime>
              <Bias>0</Bias>
              <Time>02:00:00</Time>
              <DayOrder>5</DayOrder>
              <Month>10</Month>
              <DayOfWeek>Sunday</DayOfWeek>
            </StandardTime>
            <DaylightTime>
              <Bias>-60</Bias>
              <Time>02:00:00</Time>
              <DayOrder>1</DayOrder>
              <Month>4</Month>
              <DayOfWeek>Sunday</DayOfWeek>
            </DaylightTime>
          </t:TimeZone>

          <MailboxDataArray>
            <t:MailboxData>
              <t:Email>
                <t:Address>[email protected]</t:Address>
              </t:Email>
              <t:AttendeeType>Required</t:AttendeeType>
              <t:ExcludeConflicts>false</t:ExcludeConflicts>
            </t:MailboxData>
            <t:MailboxData>
              <t:Email>
                <t:Address>[email protected]</t:Address>
              </t:Email>
              <t:AttendeeType>Required</t:AttendeeType>
              <t:ExcludeConflicts>false</t:ExcludeConflicts>
            </t:MailboxData>
          </MailboxDataArray>

          <t:FreeBusyViewOptions>
            <t:TimeWindow>
              <t:StartTime>2006-10-16T00:00:00</t:StartTime>
              <t:EndTime>2006-10-16T23:59:59</t:EndTime>
            </t:TimeWindow>
            <t:MergedFreeBusyIntervalInMinutes>60</t:MergedFreeBusyIntervalInMinutes>
            <t:RequestedView>DetailedMerged</t:RequestedView>
          </t:FreeBusyViewOptions>
        </GetUserAvailabilityRequest>

      </soap:Body>
    </soap:Envelope>
    """
    tz = pytz.timezone('Europe/Moscow')
    bias = str(tz.utcoffset(dt.datetime.now()).seconds/60)
    start_converted = convert_datetime_to_utc(start)
    end_converted = convert_datetime_to_utc(end)
    root = M.GetUserAvailabilityRequest(
            T.TimeZone(
                    T.Bias(bias),
                    T.StandardTime(
                            T.Bias('0'),
                            T.Time('02:00:00'),
                            T.DayOrder('5'),
                            T.Month('10'),
                            T.DayOfWeek('Sunday'),
                    ),
                    T.DaylightTime(
                            T.Bias('-60'),
                            T.Time('02:00:00'),
                            T.DayOrder('1'),
                            T.Month('4'),
                            T.DayOfWeek('Sunday'),
                    )
            ),
            M.MailboxDataArray(
                    T.MailboxData(
                            T.Email(
                                    T.Address(mail)
                            ),
                            T.AttendeeType('Required'),
                            T.ExcludeConflicts('false'),
                    )
            ),
            T.FreeBusyViewOptions(
                    T.TimeWindow(
                            T.StartTime(str(start.strftime(EXCHANGE_DATETIME_FORMAT))),
                            T.EndTime(str(end.strftime(EXCHANGE_DATETIME_FORMAT))),
                    ),
                    T.MergedFreeBusyIntervalInMinutes('5'),
                    T.RequestedView('FreeBusy')
            )
    )
    return root